1. Field of the Invention
The present invention relates to a musical sound producing apparatus, a recording medium, and a musical sound producing method by which the sound producing mechanism of a drawbar-type electronic organ is simulated.
2. Description of the Related Art
In a drawbar-type electronic organ (hereinafter referred to as a drawbar organ), a musical sound of a desired tone is created by nine types of sine waves having different pitches being arbitrarily combined and synthesized based on operations of nine types of drawbars indicating different footage (“16′ (′ is a symbol indicating feet)”, “5 and ⅓′”, “8′”, “4′”, “2 and ⅔′”, “2′”, “1 and ⅗′”, “1 and ⅓′”, and “1′”).
When “16′” of the drawbars is a fundamental, “5 and ⅓′” is a note that is one octave and a fifth above the fundamental, “8′” is a note that is one octave above the fundamental (second harmonic), “4′” is a note that is two octaves above the fundamental (fourth harmonic), “2 and ⅔′” is a note that is two octaves and a fifth above the fundamental, “2′” is a note that is three octaves above the fundamental (eighth harmonic), “1 and ⅗′” is a note that is three octaves and a third above the fundamental, “1 and ⅓′” is a note that is three octaves and a fifth above the fundamental, and “1′” is a note that is four octaves above the fundamental (sixteenth harmonic).
In recent years, an electronic musical instrument has become known that produces musical sounds similar in tone to that of a drawbar organ in accordance with a sine wave additive synthesis algorithm using a waveform data readout-type sound source. For example, Japanese Patent Application Laid-open (Kokai) Publication No. 2000-259157 discloses this type of technique.
In drawbar organs, each key of the keyboard is provided with switches that control the production and muting of sound per footage, and a unique musical sound referred to as a so-called drawbar sound is created by the behavior of the switches respectively provided for each footage which are turned ON and OFF in response to key depression and release operations. However, all that is achieved in the technique disclosed in Japanese Patent Application Laid-open (Kokai) Publication No. 2000-259157 is that a fundamental and a plurality of harmonics generated based on drawbar operations are synthesized by sine-wave synthesis, and therefore there is a problem in that a unique drawbar sound such as that generated by the sound producing mechanism of an actual drawbar organ cannot be generated.
The present invention has been conceived in light of the above-described problem, and an object of the present invention is to provide a musical sound producing apparatus, a recording medium, and a musical sound producing method by which a unique drawbar sound such as that generated by the sound producing mechanism of an actual drawbar organ can be generated.